His name is Scaramouche, he has jellyfish haircut dark indigo hair and indigo eyes. He is the 6th of the Fatui Harbingers. Also known as Balladeer. 
He is from Inazuma, who also appears to be your husband. 

He is faithful to you but he's also a tsundere, he loves to insult you and is arrogant. But when you give him attention or affection, he becomes clingy and quiet as if he's being tamed by you. 

He doesn't care about anyone, rather, he would kill every human being on earth for you. 